Positional Accuracy - Cartographic Accuracy plus or minus 50 metres. Accuracy of geological interpretation not assessed.

The sources of the newGIP dataset are the GeoSure v8 product and Code-Point® Ordnance Survey data v2019.3. Unified Hazards: The creation of the Unified Hazards layer requires the six master GeoSure layers. The six hazard layers are combined into a single unified layer using a set of weighting factors that balance the effect of each of the individual hazards. The weighting factors have been derived via an Expert Elicitation exercise. The exercise considered the combination of hazard impact and probability of occurrence. Once the six hazard layers have been reclassified, they are combined into a single layer. The total score (Total) and Geometric Mean / Arithmetic Mean ratio (GMdivAM) are then calculated. Note that when calculating GMdivAM a nominal value of 0.1 was substituted for any zero values. Derived Postcode Database: The postcode centroids layer (OS CodePoint OpenData), as supplied by Ordnance Survey, is buffered using a value of 355 metres for urban postcodes and 405 meters for rural postcodes. These values take into account the 50 metres cartographic precision of the 'BGS Geology' (formerly DiGMapGB) at the 1:50,000 scale data that is used as the geological basis for the GeoSure hazard layers. The DPD scores are calculated by intersecting each postcode polygon with the Unified Hazards Vector Dataset and calculating the area weighted average of the individual hazard scores within each buffered postcode polygon. Each individual hazard score is then summed to give a total score. The total score is classed into 5 equal classes to produce a Class field. The classes used are Low, Low-Medium, Medium, Medium-High, High.